In English I write "Distance from Japan to Yemem". I always use "to country". In French however, the "to" has many forms. How do I know which one to use? (I used Google translate to get the following examples:

I would say "à l'Egypte" and "à Haïti" personnaly. This question may give you some clues...
– RandomAug 29 '16 at 14:40

Thanks. I cannot read French. You mean à l' or à to replace all other forms?
– TonyAug 29 '16 at 14:44

Not one single word. We use the definite determiner in front of conubntry names. When it is masculine (le in front of the country name) you will need au. When it is feminine (la in front of the country name) you will need à la. If you see l' in front of country name you leave it as is and add à l'. In addition to link given by @Random here 's a list of country names including definite article ask s.o. in chat as you go along.
– LaureAug 29 '16 at 15:01

2 Answers
2

Only in this very specific case (saying "from one country to another") should you only use the "à/au/à l'" preposition.

For masculine country names beginning with a consonant, you will say "au"

ex: "du Japon au Brésil", "du Japon au Pérou"

For feminine country names beginning with a consonant, you will say "à la"

ex: "du Japon à la Belgique", "du Japon à la Colombie"

For all country names beginning with a vowel, you should use "à l'"

ex: "du Japon à l' Angleterre", "du Japon à l' Espagne"

There is no easy way to remember whether a country is masculine or feminine.
Native speakers just learn it by heart...

And as if it was not complicated enough, there are exceptions to this rule.
Some country names, mostly islands but also plural countries like the U.S., act like city names.
Then you just use "à", or "aux" if it is an archipelago or plural.

You need to learn the article (or the absence of it) in order to guess how to say from... to. Beware: I'm only talking about that specific context. I'm not talking about position (I live in France), destination (I go to France), or origin/source (I'm from France). It would be a different translation to say I travel from Japan to France or I have moved house from Japan to France. Here is only about the distance.

La (feminine) = de la... à la...

La France, la Birmanie

De la Birmanie à la France

Le (masculine) = du... au...

Le Japon, le Congo

Du Japon au Congo

L' = de l'... à l'... (masculine or feminine with an apostrophe, starts with a vowel so le and la become l', the only exception is le Yémen which is used as masculine above)

L'Allemagne (f.), l'Iran (m.)

De l'Allemagne à l'Iran

Les = des... aux... (plural)

Les États-Unis, les Pays-Bas

Des États-Unis aux Pays-Bas

No article = de... à...

Cuba, Israël

De Cuba à Israël, d'Israël à Cuba (note the d' because of the vowel)

As you can see, there is no use of en. Haïti is in the last group, so it's D'Haïti au Japon (the h is silent in Haïti, so it's like it is starting with the vowel a) and Du Japon à Haïti.

Bonus: is there a way to know if a country is feminine, masculine or else? It seems that yes: